Note: Descriptions are shown in the official language in which they were submitted.
Tbi~ vention relate~ gene~ally to the field ~f tru~ed radio ~ em~
~d ~p~cifically to ~ meth~ a~d me~ c~f ~)r~3Yidi~ 1mple~ di~p~h
tru~ked ~yatem operatios whil~ ~go pr~id~ dupl~x ~e~epho~
i~t~e~ Op~iQtl i~ o~ b~criber u~it. Thi3 h~ io~ o pr~id~
a m~t~aod a~d me~ Q} impleme~ impl~ di~patch/i~terco~ecs ~d
duple~ i~terco~ne~ ~mmu~ic~ ~hen c~ m~y b~ iiitl~t~d froln
¢ither tho landline or sub~iber UDit, whil~ rem~ comp~tiblo with
eo~re~l~io~ npleI ~ru~ked ~ys~em oper~tio~.
I~corporatillg a telephone i~terco~ect call mode of operation onto a
trunked ~y~tem ha~ general~y be~ str~d by the ~imple~ (voice a~d
d~ta ~ g) n~ture of ~run~ed sy3tem ~ub~cribes u~it~. Similarly,
gig~alJing ~d e211 proce~sing by îi~ed-end colltrol equipme~t i9 ~lao
~imple~ f~mat~d. While the i~odu~ioTl ~ duple~ vGi~/RF-c~p~bl~
subscfiber u~it~ u~il~ 9imple2 dhta 9i81la~ 3 with fi~ed e~d ~tro~
e~uipmef~l imprGYe3 the grade o~ u~e~ i~te;rco~ ~er~oe, their u~e
r~ yna~i~ d ca~ h~ si~l~
w~ pl~9i~ I CUl`~ ~y ~
Briefly d~ibed the pl'e3@n~ in'Veg~ D~ OOnteZllplate~ a meth~ 3:~d
mclul5 ~ p~oYidi~ duple~ iel~phone interco~e~ ~ef~ic~ in ~ub~iber
u~t3 which a~e o~herwi~e oper~ion~l on oonveatio~ runkecl radio
sy3tem~. Acc~ to ~he principle~ ~ th~ ~re3e~t inve~ti~ duple~
capable su~crib~r u~i~ ~pera~e3 with a ~lurality ~ duplex tru~ked
repeater~, R tru~king oe~tral co~trol unit, ~d a teiepho3le i~terco~e~
con~rol u~i~ ul a~das~ce with a pred~termin~d 9i~ cheme. Th~
~i~nalling ~cheme of the prese~t i~ve~tion i~ ~ti~ted by a m~ile u~it
tr~smi~ g a~ inbou~d ~ignaLLi~g word (ISW~ to a ce~tral control u~l, on a
predetermi~ed fre~uency, wherei~l th~ ISW indic~ate~ tha~ duple~
inter~nne~ call serrioe has bee~ fequested. The mobile the~ reoeive~
outbou~d signallin~ word (~W) from the oe~tr~l co~tro~ u~it, wherein th~
OSW co~3tites a 8rant for th~ mobile u~it to ope~ate on a$l a~i8ned
frequency. The mobile then tr~smit~ a co~ect tone for a predetermined
pe~iod to the oentr~l cotltro~ u~sit, o~ an a~sig~ed frequen~y, while
con~urrelltly reoeivi~g ~ lo~7-speed h~Ddsh~ke ~ al transmitted fro the
cen~r~l ~ntrol uni~. Ne~t, thc mob~l~ u~ concurreIl~ly tr'aD.9mi~3 a
~equential DTMF 9ig~1al fOI' ~I predetermined period, a~ the termi~tlo~ of
~he conne~ tone, whlle al~o ~iving a l~-speed hand~ha~e 3ignal,
OI63~
S~e~i~lia~ 2
~hese~D tho DTMP ~i~nal ~mpri~ ~e~ir~d teleph~e i~ r~ne~ dia~
i~fof~ati~ ~d fi~ c~curre~ly tran~mitt~ a voic~ and ~nnec~ tone
~i~nal ~hil~ re~i~i~ a voi~ ~i$~a~ cDGnbined wilh said low ~peed
h~d~h~ks ~gn~l, al the tef rni~ation ~ ~aid DTM~ ~ignal.
~ ordi~sly, it i~ an object ~f the pre3e~ en~ioil to prwide duple~
t~lephone i~terco~ 9@1'Yi~æ, 9implc~c telcphGne inter~ and
eo~e~tio~al sim~le~ tru~ked radio ~ervioe u~ilizi~g common co~lrol
equiptment.
It i~ ~other obJect of th~ pre~e~t ~e~tion ~o provide ~ ethod ~d
me~s for u~ifyin~ the ope~atio~ Qf a hybrid commu~ic~Lion sy~tem.
It i~ ~till a~sther ob je~ ~ the pre~e~t L~ve~tio~ lo provid~ a ~runked
radio ~9tem which is compatible ~ith duple~ t~lepho~ ~enric~.
It i~ 3~0ther object ~f the pre~ent i~vention to provide a method and
mean~ of providing DTMF signalljng over a simpleI tru~lL@d radio cha~nel.
Figure i i~ a bloc~ dia~ram of a trun~ed radio ~yYtem which is
interfac~d to a oo~ventional duple~ tclepho~e sy~em.
Figure~ 2a a~d 2b are ~imillg di 8ram~ ~howing the de~ails of
illbound and outbound ~ig~Flling word3 used i~ accorJa~l~ with the
teachin~3 of the prese~t i~ve~ioD.
Figure~ 2c, and 2d are timing dia8ram3 showing the ~equenlial
signalli~ between ~ ~ub~iber unit and the sy~tem central control u~t
which m~y be en~ull~ered in a typic3.1 3imple~1 ~runked radio 3y~tem.
n 1 63H
SpedS~ 3
F~ur~ 20 is ~ ti~ dia8r~ ~h~i~ th~ ~eque~tial 9ig~
bet~ee~ a ~ub~ib~r u~it a~ gyg~ ~1 ~atrol unit ~hich ~ould
b~ e~coll~tored i~ the ~llpl~ t~e~/ ~i~plltch ~su~ed radio syYtem
~f ~e pre~ent in~efltio2l.
~ i~ur~ 3 i~ ~ m~e detsile~ bl~l6 diB~ra~ detaili~ ~be co~stru~jo~ Qf
the f~ed-si~e p~ n of th~ tru~lked r~dio ~ysl~m ~ Figurcg 1 a~d 2.
P~ur& ~ i3 ~ ~chematic a~d bl~clc diagr~m of the ~tral co~trol u~t
Figuro 3.
~ i8ur~ 5 i~ a ~chem~tic dia~ram ~ tbe iDter~n~ co~ uI~t o~
Fi8ur~ 3.
Figur~ 6 i2 ~ ~chematic and block dia~r~m Qf th~ subxriber u~
configuratio~ ~hi~ may be u~ed iR accordaD~ ~ith the teachi~g~ af the
prese~t i~ventio~.
Figur~ 7 thfough 12 are flow dia~ram~ detailinx the oper~ the
~ub~riber ur~t microprooes~ igure 6.
~bLb~
Figur~ a bloclc diagram o~ a ~u~ed radio sy~tem which i~ coupled
to a co~on~ l telepho~c i~teroon~ em. The tru~ed la~ld mo~ile
radio ~y~tem 100 ooD~i~t~ ub~criber u~t~ 102, 104, which may be ei~her
mobil~ or poftable uiit~, a plura~ity oi ~uD~ed repeater~ 10~, ~nd a
tru~d oe~tral controJler 11 0. Th~ ~ruD.~ed oe~ contro~ef 1 10 i~ al~
coupled to a c02l~01 channel tral~xe~v~r 108 which transmit~ and reoeiYe~
00 163H
Spe~
?. C~ ? ~ ~
~trol i~mati~ o~ a xp~t~ ~reqlJ~cy. l'he ~u~ked cen~ral ~t~oller
110 a~d tru~ed rgpeatcr~ 106 ar~ ~ed to ~ ~ter~leCt
co~trol un~t which ~n~ol~ the ~ru~cd re~a~r~ d th~ public s~itchsd
telepho1le ne~wor~ e~fa~. The trunke~ ras~io gy9t~m u~ilize~ additioaal
trun~ed reps~a~r~ a~ ~i~a~e~ by t~e number ~ chan~el~ operatiYe oll ~he
truD~ed sy~tem. In ~he quiessent stat~, ~11 3ub3criber unit~ 1~2, 10~
monitor the outbo?3u~d f~qu~ncy ~ the trun~ed ?~ ~p~t~r I ~?8 Wllich i3
des?~ated a3 th~ Gon~ro1 cha~e1.
~ f~rri~8 n~? to ~?~U?. e 2~, to ~tab?Li3h ~ di~pat~h c~l b~??ee~
group of u~its opera~g on the trun~ed ~r~tem, a ~ub~criber UDit 102 ~e~d3
a d~ia pacl~e~ caLled an Inbouhd Sig~alli~4 ~ord" (IS~) 'rhe ISW i~ ~h~w~
in Figurc 2~ ~d il co~t~ the re~uesti~l~ uiit ~ u~ique ID ~e, tc~ ti~g
of ~ fleet IlD, a~ indi~???idual ID, aDd a subfleet code ~dicatiD~g to which
group of u~its it w~t~ IO tal~. The ISW al~o co~t~ a unique c~ll type
code uhich i~dicate~ Ihat a disp~tch call i~ ~he type ~ eall deii~d. The
reques~ i~ forw~rded to the oe~ troller 110, which deoode~ the
r@que9t, alld tran~mi~ a data pac~et called an Ou~bou~d Si~alling Word
(OS~ ~o all ~ub~criber u~ 102, 10~ which are monito~ing th~ outbou~d
control chan~el. The OSW i~ a cha~el ~ra~t which co~tai~ the ~ubfleet
code, ~h~ reque3t~g u~it 9 ID code, and the voi~e channel number a~ ed
for the co~versatio2l. Th~ OS~ cau~es the r~questing UD~t to mo~e ~o the
voice cha~el and commence transmittfflg, alld cause~ all mobile3 wiih
matchi~ fleet and 3ubfleet ID ~ ~o mo~e lo the voice chan~el a~ e~
uni~ thi~ way, a 8rouP o~ ~ubfl~t" call co~lversatio~ et up. If all
O~ 1~3~E
Spe~
~3f~3~3
~h~ Yoi~ ch~el~ n, u~ th~ oe~tral co~ltroller 11 0 send~ th~
requ~ bacsiber u~ 102 a Busy OS~
In lhe trun.~ed ~dio ~y~te2D. of ~he ~re~e~t i ventio~ telephotl~
i~terco~es~ ay b~ e~tablighed on ~hle tru~ced radio ~tem from
ei~her ~ mobile u~t or a la~ based telepho~ terconnect caller. 1~ ~he
ca~e o~ call~ ~tiate~ from mobile unit~ IS~V reque~t i~ se~t a9 fo~ the
mobile to move to the voioe ch~nel ~hil~ at the ~am~ time dir~g thç
intereomlect control u~it 11 2 ~o e~tabli~h a coDne~io~ from ~hc
eorre~ponding repeater to the lalld ba~cd telepho~e liil~. A duple~ unit
receiv~ a chaD~el gr~t al~o causes a duple~-capabie co~lroller to
dynamically reoo~fi8ure it~ audio ~ignal path~ for dupl~ audio rou~g. 1
th~ preferred embodime~t of the pre~e~t invention, a ~ub~iber ui~t lQ4 i~
also co~figurable to allow ~imple~ i~terco~nect telepho~e call~. If the
central c~troller determi~e~ that a~ i~ter~ect cali should hOt be made,
~he oe~al co~troller I 10 ~e~d~ the reque~ti~g unit 102 a~ crcoDn~
bu~y OSW.
For call~ initiated from the land li~e, the i~ter~o~ect control unit 11.2
genera~e3 8 request to the cen~al controller 1 10 for a particular mobile to
be a~i8~ed to a~ i~tercoD~lected voice cha~el. The requlest take~ the form
of an ISW with the identifica~ion snd call type inforlhatio~ as de~cribed
above. If a channel i~ svailable to be assigned, a trallsmit OSW" i9 ~ent to
the tarBet mobile 102 or 104 i~ a~ effort to determine if i~ i~ ac~ively
turned on or opefational. If it i~, a "ring OSW" i9 sent via the outbound
control channel to the target mobile 102. A~ in the c~e of the mobile to
CM-OO I 63H
Sp~ 6
land call above, this central contro]ler audio routing is
adaptive to the type of target unit service reques~ed. If the
central controller 110 determines that an interconnect call
should not be made at this time, a busy iden-tification is re-
turned to the lar,d-line caller. If the target mobile does not
respond to ~he transpond OSW by issuing an "acknowledge ISW", the
land-line party is re-turned to a pre-determined signal indicat-
ing this and the central co~troller are terminating the call.
Referring now -to Figure 3a, there is shown a block
diagram of a trunked radio system coupled to a telephone inter-
connect system which embodies the features cf the present
invention~ The present invention operates with, but is not
limited to, the trunked radio system of Figure 1 with the addi-
tion of the telephone interconnect control unit 112. A mobile
radio suitable for use as a subscriber unit 102, 104 in the
trunked radio system of Figure 1 is shown and described in
detail in Motorola Instruction Manual 68P81064E20 entitled
"Privacy Plus 1000 Radiotelephone". A repeater suitable for use
in the trunking system of Figure 1 is shown and described in
Motorola Instruction Manual 68P81038E85 entitled "Micor Trunked
P~epeater", and may be obtained from the Service Publications
Department of Motorola, Inc., 1301 East Algonquin Road,
Schaumburg, Illinois, or from Motorola C & E Parts, 1303 East
Algonquin Road, Schaumburg, Illinois.
Referring now to Figures 2~ and 2b, there is shown a
timing diagram detailing the configllration of the Inbound
and Outbound Signalling Words
de~eribed i~ Figu~ 1. T~e Inbou~d Si~nallins ~Md ~s~pri~e~ a 21 bi~ da~
pacl~o~ ~hich i~ ~ent from ~ ~esue~ti~8 ~ub~ib~r to ~he ~ troller
whe~ a chan~el a~9i8~mont i3 r~uired. ~he f~ eea bit~ corre~ d to
an id~tific~ticn field, ~hi~ id~ntifie~ ~ particular u~it ~ ~lee~, ~ubfl~t, and
indiYidUal addres~ a39ignmetlt~. The rem~ fiv~ bits of the 21 bit
paclce~ identify the Iype af c~ ~ llle~ag@ to be communicated o~ thc voic~
channel.
Referri~g ~97 to Fi8ure 2b, the eo~igur~tioa of the Outbound
SignaLli~ word i~ 3hown in detail. The Outbound Signalli~ Word i~ u3ed to
eommunicate cha~l a9~ignments from the ~ral ~rol u~it ~o Ihe
regue~t~ng sub~eriber units.. Thc Outbound Si~ g Word compri~e3 a 27
bit data packet wherein the ~irst ~i~tee~ bit~ are u~ed a~ ~ sub~criber
ide~Iifac~tion field. The remiaini~g 11 bit3 commuiicate chaamel
as~43~meaS~ or 3tatu~ matio~ to the reque~til~g mobile u~it.
Pi~ure 3 i~ a mMe detail~d ~ diagram cd the tru~lced radio ~y~tem
~f F~gure~ 1 ant 2. The truD~ed ~yttem ce~tral oontroller 110 of Figure 1
con~i~t~ of a c~ntral si~e controller module 302 which commu&icate~ with 3
receiver site corltroller module 304, a tran3mitter site c~trol module 310,
a~ld the intercon~e~ oo~trol module 352. CommuDicatio~ betweea ~he~e
module~ a conve~ 232C serial interface. The ce~tral ~i~e
eo~oller I lO receive~ IS~1V's ~rhich are reco~ered from the reoeiver site
controLer module 30~. The re~iver site cs~Iltroller 304 i~ coupled to a
plurality of recsiver interfa~ board~ and a~ bound reoovery board 308
through an addre~ data bus which eommunic~tes the decoded r~pe~ter
C~-oo 163H
Speci~
.i .Y~ 3 `~ ~ ~`~SI 3
r~ .3~ f'e~ b~d 3~ t~r~
~6 ~ ~e~ ll~ 3~.
A~er th~ ISW h~ b~ r~v~d, ~h~ a~ roll~ modille
302 re~ d~ to the gequ~i~ u~t ~y 8e~rsti~ a~ ~W ~t~
chann~l a~s~nmea~ ~. T~o ~ CQmllaU~li6~ed ta ~h~
reque~ u~Liit vi~ ~he 3erial ~ li~ coup.led betu~~ tral gi~e
rol~r 3~2 a~d ~he ~r~smit~er ~ ~trol5~ module 31û. Af~es th~
tran~mit~r ~ in~er~ board ~i2 r~i~e~ th~ ~W ïrom ~h~ oe~al
c~sro1 ~aodu1~, ia i~ p1~aed o~ ~ ~ddr¢s3Jdil~a bu~ ~hich i~ ~e~
~mm~y ~i~h a plurali~y o~ mi~ter ~ter~ac:~ board~ YJhi~ ultimat~ly
c~trol the repea~ers 316, 318, 320, e~c 1~ re~ o to a~ ISW, the c~r~l
ol u~it 302 may sdditio~ally in3tfuct the int~rco~ ~ol UDit 352
to int~rco~e~ a tçlepho~ to ~ particular repe~ter. CotamuDic~tiol~
between thg ~ntral c~trol modul~ and the i~terco~ne~ co~trol module i9
~ia a~o~her RS-232S ~ interfa~. The e~ circuit c~u~a~ion and
detailed d~ip~ d the ope~ation ~ the ~tral control u~t liO i~
de~cribed L~ ~jun~o~ ~ith Figur~ 5 a~d i~ further de~cribed i~ Mo~ol~
In~tructioa Mam~al e~litled 'S~u~ed System Central Controlle~,' Numbe~s
68P810~7E~0 and 68P81066E60, zvail~ble îrom the Service Publi~tions
~p~nm~ ~ Mo~ol~ c., 1301 Ea~t ~lgoIlqu~ Roa~, Sch~umb~r~,
Illlnoi~.
The i~ter~nne~ c~ntro1 u~it 112 of ~i~ure~ 1 co~ h~
inte~ ~ contro1 modu1e 352 which co~trol~ the OpefatiOl~ ~ ~he ~itch
matri~ b~ard~ 35~, the i~ter~D~ line in~erface bo~rds 362, 364, 366, a~d
1 63~
S~ech'~sb~ 9
3~
the trunked repeater inte.rface boards 356, 358, and 360. The
interconnect control module 352 co~nu.nicates with -the switch
matrix 354 vi,a a parallel address/data bus. The interconnect
control unit communicates with the interconnect line interface
boards through the matrix 354 and a serial link which couples
the phone line in~erface boards 362, 364, and 366 with the
switch matrix 354. The interconnect control module communicates
with the trunked repeater interface boards 356, 358, and 360 via
the auxiliary pa~allel address/data bus coupled between the
s~itch matrix 354 and the trunked repeater interface boards 356,
358, and 360. The phone line interfac~ boards 362, 364, and 366
are additionally coupled to telephone register intexface boards
368, 370, and 372. The telephone line interface boards 362, 364,
and 366 are used to generate and decode the various signalling
tones which are required to control the operation of the tele-
phone interconnect system. The registered interface boards are
used for signal conditioning and level control before the tele-
phone signal is applied to the switch matrix 354. The operation
of the interconnect control unit 112 is descxibed further in
conjunction ~ith Figure 5. A detailed circuit diagram and
operation of the interconnect control unit 112 is shown and
described in Motorola Instruction Manual 68P81063E20 entitled
"Trunked System Central Controller", available from the Service
Publications Department of Mo~orola, Inc., 1301 East Algonquin
Road, Schaumburg~ Illinois.
When a given telephone interconnect is requested
from a subscriber unit, control module 302 instructs the
interconnect control module 352 to
ob~ a tel~phon~ ~ti~ Yia ~h~ p~ae I~L@ ill~er~aoe ~o~ d ~upl~
th~ ph~ o a ~p~i~i~ repea~er. Th~ pho~ e i~terfaoe bs~d 3U~pllt
362, 3~, or 3~6 ~ ~e ~unk~d fepea~er inter~aoe bo~rds 356, 358,
360 are the~ couple~ via the ~itch ~a~ri~ 35~. The ~u~pu~ af th~
p~rticul~r ~ru~ed re~ater ~t~f~ board i3 the2l coupled to a p~icular
~ru~ed repeater a~ ~strucS~d ~y t~ mt~rs~ con~rol u~t. Tel~ph~
er~t c~ either requ~ d or t~eted ~ ~ du~le~ sll~iber unit
o cau~e r~i~ed audiD from 3am~ to b~ m~ed ~ith l~dlifle ~udio
YiD~ the tru~ked repe~e~ L~te~fa~e board~ ~56, t58 0~ 460 ~teild of bci~
d~cc~y ~an~mi~lqed via re~ealer~ 316,318, o~ 360. Audio ~trol circui~y
loc~ted on inte~fa~ bo~rds 356, 358 o~ 36Q e~tabli~he~ thi~ audio 8at~ via
trunk¢d repeater~ audio line dri~ ~cuitry, ba~ed up~ ~mm~d~ from
the L~tercomle~ eontrol module 3S2.
If ~ inter~ect i~ required from la~d line to a m~ile u~it, ~he
telepho:lle i~erf~oe boards 362, 364, or 366 de~ect the pho~ ~ignalli~ on
the la~d line and th~ notify ~he ~te~ ect co~trol u~i~ th~ a call i~
wai~ on line N.' Thi~ me~a8~ i~ communicated via a ~erial li~. The
inlerco~ec~ con~rol then requ~s~3 a repeater cha~nel by placin~ an ISW on
the ~erial link coupled between the i~tercoD~ect co~trol unit and the 3y9~em
centr~l co~foller. The ~ys~em then a~sig~ a repe~tef and ins~ruct~ Ih~
int~rc~ed co~rol module 352 to couple t~lco line N" to a specific
repeater via ~he switch ma~r~ 35~ a~d t~ ~u~ked repeat~r i.qterïace~ 356,
35~ 360.
Telepho~e in~erconne~ c~ for both mobile-i~itiated a~ l~d line
C~-ûO ~63
Sp~f~
f ~ " ~ ~3 ~
iiiti~ted c~ rg termina~ed by th@ c~al ~ll~OIlef 1 10 as~xdi~g ~o the
sam~ me~ vhe~ei~ the oe~ l u~it 110 ~ the m~ile u~it
and ~he land line intefco~nec~ ~h~t ~he call i~ about to be termi~ted by
~end~ comfn~d~ ~hich i~ u~ th~ er~i~e~ control u~it to term~nate
the intercon~lect a~d i~trucl the mobile u2~t to returs ~o mo~to~g ~h~
c~atrol ch nnel. The mobile u~it m~y term~ate ~ i~terc~ y
send~ an e~d of c~l 9i8I~al in the fof m of a~ IS~V, to Lhe oe~ troller
110. 1~ a ~imilar f~hio~, if the tçlepho~e ~ter~D~ caller termi~ es t~e
call th~ intercoDnect co~trol unit 1 12 ~ignal~ the end Qf the int~r~nect by
~end~ ~ e~d ~ ~all ISW to ~he ce~tral co~trol u~it I 10
Referr~ now to Fi~llre 3b, there i5 ~howIl the Llteroonnect call
timo-out rou~i~e. Whe~e~er a~ ~ntercoDnect calJ i~ a~sig~cd, R ti~sr ~he
len8th ~1 the the i~terconnect call limit i~ started. .~ccordi~g to Fi8ure 3b,
Item 384 i~ 3elected wheneYer a ~he timer e~pires. Whe~ the timer ~pire3,
the ssll i~ termillated after war~ tone~ are ~ounded to th~ mQbile a~d
la~d li~e caller~. Item 384 ~elec~s deci~ion 386 which e3&mine~ the
repeate~ output 106 receiver to determine whethe~ the pa~ti ula~
~ubscriber unit i9 curre~tly keyed" o~ naitti~g. If the mobile is still
keyed, decision 38~ ~ele~ deci~io~ 388. If the unit i9 duple~, ale~t ~o~e~
are ~e~t to the 3ub~criber via item 392 aad the call i~ terminated via i~em
394. E13~ deci~io~ 388 wait~ to~ a sub3cribef to de~ey befote ~tarting ~he
call termination 3eguenoe.
Referrin8 now to Fi~ure 4, there i3 3hown a~l electrical sehematie and
block diagram of the central contro~er 110, a~d the telephone interco~nect
Q~-OC I 63H
S~ 2
~l~t~ ~ 4 ~
a~d ~lephsne ~llter~3Qn~ co~troller l~Q ~e utili~e the 31~me pfOoe~9
~nit ~he c~ rol llnit Comp~i~9 a ~neral pll~ miGfOp~ 3~ 4~
whi~ interîaces with a bu~ buffef ~0~ a~d ~ bu~ tr~ns~iver ~06. The
mic~oproce~o~ ~pp~t3 ~h~ b~3i~ operatio~ ~ ~h~ oe~a~r~l co~trol u~i~, a~
well a~ the oper~tio~ ~ th~ telepho~e ~ter~e~ ~ntrol unl~.
Microp~ooe~ 402 ~a~y b~ ~y ~eral purpose micropr~e3~ ~uch ~ a
Motorola MC6B09 a~ailable from Moto~ola Semico~ducLo~ c., 3501 ~
Blue~tei~ ~oule~ard, Augtln, Tf~a~. The bu~ buffer 40{ i~ ~dditio~lly
~upled to bu~ buffe~ 408 which pr~vide~ addre~ inf~m~ti~ ~o the
peripheral i9te~a~ ~dapter (PIA) 412, the ra~dom ~3~ memorie~ (RAM)
41~, ~d 416, ~he re~d-o~ mem~ (RO~) 411~ and ~h~ asynchroIIou3
interfa~ adapte~ ~ACIA) 424. Bu9 tran~ceher 406 communiea~e~ data
betwee~ the micr~mputer 402 a~d th~ periphe~ terfaoe ~dapter ~
the RAM memories 41~, 416, the ROM ~18 and the async~ro~ou~ in~erfaae
adapter 42~. The Pl~ 412 i9 additio~ y coupled to a fron~ panel di3pl~y
which serve3 ~9 a sy~teaa ~dicato~. The a~y~chronous in~erface adap~er
convert~ the dat~ pfe~e~ o~ th~ data bu~ to th~ ~eri~ ~ignal~
eommunicated betwee~ the cc~tral corltrol module and the receiver ~ite
controller, ~he tr~mitter ~ite eo~roller an~ the i~tercon~e~t ~ntrol u~i~
112 of P~llro ~. The peripheral ~nterfao~ adapter 412, the RAM memorie3
41~, 416, the ROM 418, and the asy~chronou~ i~terfac~ adapter 42~ may be
a~y of ~everal of~-the-shelf compolle~tY Whi&~ are de~igned to interfaoe
w!th the microoompouter de~crihed abo~e.
Cal-00 1 63H
~p~f~ 1 3
Ref~ ~ uro ~, ~e~ h~vQ ua el~ri~al ~he~tic and
block di~ra~ ~ lh~ t~r~na~ cs)ntrol unit 112 ~ Pigure 2. ~he
rcon~ co~trol u~t co~pri~ ~ g~eral p~ur~ micropfoce~sof 5Q~
w~ich inaerfa~ with a ~u~ ~ufrer SO~ ~d a buls ~ xeiver 506.
Micropr or S02 may be a~y ge~r~l purl~o mi~opro~sso~ ~ueh ~g a
Motorolf3 MC6809 ~ailable from Motorol~ Se~nico~ducto~, Inc., 35DI Ed
Blue~tein Boulevardi Aust~, Te~a~. The bu~ buf~er 504 i~ addition~lly
ooupled to bus bu~fer 5a8 which proYides address i~rmatioll to the
peripheral i~terface ad~pter 512, ~12 ru~dom ~ m~maries 514, ~nd
Si6, the read~y memory 518 aIld ~h~ a~y~chroIIou~ ~erf~ee ~dapter
52~. Bu~ iver 506 oommu~e~te~ data bet~ he mi~ooompu~er
502 and Ih~ peripheral i~tergnec ad0~pter 5 1 2, the R~M memo~ies 5 1 ~, S 1 6,
the ROM 518 and ~h~ ehr~ou~ ~terface ~d~pter 52~. The Pl~ 512 i~
addition~l~y ~upW to a fro~t pa~el di~pl~y 522 ~hich ~efve3 u a sy~tem
~dicatof, a~d a parallel d~t~ bus which couple~ the pho~o li~e interf~c~
circuit~ ~62, 464, aDd 466 d` Figufo 4. The i~terconnect costrol modul~ i~
al~o coupled $o the switch matri~ 45~ and ~ru~ed repeater interfac~
board~ 456, 4~8, and 460 of Figufc ~ via the dat~ and add~e~3 bw ou~put~
of bus buffer 504 ~d bw tra~l~ceiver 506. The asynchronow interface
adsp~er coaver~ tho dat~ pre~ t on tho dat~ bu~ to the 3eri~1 ~ig~
communic~tcd be~een the oe~tral con~rol m~ule and the i~terco~ec~
co~trol UDit 112 of Figurc ~. The peripheral in~erface adapter, the RAM
memorie~, the ROM, and the a~ynchronous interfaæ adapter may be any of
seYeral readily available componeQt~ which are do~ ed ~o ~terfaoe with
the microcompllt~r de~cribed abo~ç.
00 1 63H
Spe~flca~o
~ 5~ ?~ ~ ~
Tl;~ operati~ ~ the pre~t i~Y~ltil~l uill b~ di~u~d i~ îull detail
belo~. Bri~, ho~r, the op~i~ of l~h~ pre~e~t ~nYen~ioh m~y b~
sumsn~Lzed ~9 fo~
All ~c~iYa~ed ~ruDked ~ubscribe~ un4t~ whic~ ot curre~tly
pro6e~ caLi ~e direc~ed by ~ inter~ radio ~n~ol pf~ to
C~21tillU9U9~T r~ive a bin~ e~led d8t~ stfea~a f~om the Cen~l Sit~
Controller (~C). Tbi3 ~equenoe i~ 9h~ i~ line~ ~, E, ~d I of Fig~are~ 2c,
2d, asl~ 2e res~Yely~ This d~ta ~tream OOn9i9t~1 of a ~e~u~nce of data
p~et~ ted o~er ~ 9i~çlo RF ehaQDIel. Th~ d~t~ ~y G~tii~ sp~ific
informatio~ ts b~ u~ed by o~e Of mor~ ~ub~criber~ in ~i~ reque~t
for, ~ comme~c~ ~ ~ctu~ call o~ a dedir~teâ voice RF repe~ter h~n~el.
he ~bsence o~ a~y u~er-Ypecific c~ll gra~ inf~mation, th~ data ~tre~m i9
u~ed by a radio f~ the purpose of bit~ ~ it3 inter~nl d~ta rec~ve~y
cir~ui~ry.
F~ call3 ini~i~led from ~ubscribcr u~ IS~V reque~ i9 ~e~t fro~
the u~t to th~ cen~r~l c~troller 110 a~ e di~pa~ch call3 above, e~cepl
that the call typo codc is th~t for a~ i~ter~ e~ cal~. Th~ ce~tral
controller ~ends an OSW "channel gra~t to the requesti~ ~ubscriber,
saus~g it to move to the voice chan~el, while at the ~ame time dLrecti~g the
i~terconn~ contrd u~it to e3t~bli~h a con~e~io~ from the ~respo~ding
repeater to th~ l~d ba~ed telephone li~.
~ or call~ i~itiated from the land lin~, ~he ifl~erc~ contral u~
8enerate~ a re~ue~t to the, central eontr~ler ~or a particul~ ~ub~criber to
be a~si8~ed to an interco1l~ected voice channel. The req~e~ t~e~ the form
~-oo t 63N
~ n IS~ ~i~h ~e identific~ ad cDll 1.y~ i~f~m~io~ ~ de~cribe~
ab~æ. Ig ~ cha3~ a~iiabl~ ~ b~ a~si~ed ~o the i~tereon~e~ c~lL a
rin8 OSW' i~ sen~ vi~ outbou~d ~ol ch~el to the ~e~
sub~iber.
O~oe tr~nsferr~d ~o ~ voioe chan~l, thl~ pre~e~t ~v~n~io~l cau~e~ ~h~
t~8et ~u~ibe~ îo b~ a u~ e duple~ dat~ ~ig~ p~ot~l
concurren~ to the RF cluple~ o~eratio~ ju~t be~u~, whe~ a d~ple~ telephone
~tesc~e~ call i~ ~eing pro~ssed.
Th~ o~ratio~ o~ Ihe ~esent inven~io~ i~ be~t de3~ribed ~ ~wo pnrt3.
Tb~ ~irst por~io~ bel~ i~olves an oper~tio~ rvie~ o~ th~ ~ub~iber
u~t~ lud~ a fu~ctio~ell deg~i~ti~ ~f circuit el~mo~t3 ~D~ rela~ed
co~rol fu~ . The second pOftiOI~ af the descripti~ relate~ to the ~ey
co~trol ~l~osi~hns~ which o~erate ~ ~ccorda~e with the te~ g~ of the
preseat i~e~tio;l.
~ eferr~ ~O~f to Figure 61 there i3 ~ho~ an el~ical sch~m~tic Qnd
bl~k dia~ssE~ ~ a ~ub~cribel~ unit 1û4. I~ th~ operatio~ of the 3ubscriber
unit, ~ RF sig~ ei~hcr reeei~ed or tr~mitled ~hrou~h the duple~ filte~
eleme~ 602. The duple~er filter element 602 is comprised of two
subs~ion~, which pro~ide ~verload pro~ection to reoeiver circuit 608
while co~curre~tly rnuting ~mplified tran~mi~ter e~ergy vi~ circui~ry 604,
602, a~d to allte~ 616, thus proYidi~g RP duplex operatio~.
In the ca9s of a mobile ~o land call, onc~ the 3uscriber uni~ 104 i~
transferred to the ~ra~ted' voice cha~l for a duple~ erco~nect call,
the pre~e~l inYention causes the reque~ting sub~riber unit ~o e~ecute a
C~-OO I 63
S~ 1
duple~ dat~ pa~o~l ~ ~pe~ali~ ~ra~ Ih~ oe~tr~l ~trolle~ 110
Fi~ur~ I f~ ~he du~lo~ ~ dupl~ ope~tio~ Th~ gub~ihes~ u~t
1 G~ ~currently ~g a~d ~ ~s ~ ive~ dat~ that h~ bee~
demodula~ed ~ ia reoei~e circuitr7 608, ~ ered vi~ reseive filter 6û6, and
pr~e~ed ~ia ho~t p~o~ 61~ ~bis ~r~ ~ ; sho~ e~ ~ ~d L Qf
Figur~ ~e. Micrc~mputer 61~ raay be a~y ge~eral pur~3~ ~i~o~aputer
such a9 a ~o~o~ola h~C6803 a~ail~ble from Mot~ol~ Semi~ondu~r, Inc.f
3501 Ed BllJe~tein ~ule~Jasd, Au ~. Te~a3. Mi~ompute~ 61~ ~ the
~ourc~ of a ds~a or to~e tfa~mitled sig~al th~t i~ it~ed by tho
co~troller 1 10, f~ purpo32~ o~ estab~ g ~d m~toring ~h~ pr~3e~oe
~ub~criber a~iYi~y o~ ~he 8r~t voiGe cha~el. Thi~ slg~ ~upled to
~u~nm~ circui~ 610, ~hat i~ al90 u~ed a~ a commo2 ~ode f~ oth~r 3i~1
output~ from proce~sor 614. The signal is thg~ filtered Yi91 eno~de îilter 612.
Thi~ fil~er, alo~g uith inpu~ filter 606, i3 Cap51ble of operats~g with one of
~wo ~el~ble frçque~cy characteri~ti~ vi~ ~ 618 co~rolled by
pro~e~sor 614. Por the pre~nt ditcus~ion ~volYing ~ duple~ insercoDnec~
call type, filters 606, 612 are c~ ured to pa~ ~ig~ havi~g low or
~ubaudible ~pe~ral c~mponent~. The filtered tran3mit tone signal i~ pas~ed
to ~ra~3mi~ circuitry 60~ for modulatiIlg an R~ c~rrier, which iY amplified
a~d coupl~d to ~ input pOft of dupl~ fii~er fiO2, which i~ in tur~ coupled to
S ~ ~.
A dial-to~e i~ ~upplied to the radio sub~iber user onee ~he audio i~
u~muted. I~ re~ponse to this, ~he u~er may either enter telephone nu :nber
di8it~ via ~ DT~hP en~der or ~3 i~l th~ preferred embodiment o~ the
~-0û Ig3H
Spes~ a ~7
e~io~ ~ Pi~ur~ 6. The circuitry i~ Fa~Uf~ ca~abl~ ~f outputti~ lo~
~ t~ae9 ~ mi~ , t~ , ~h~ t~
freque~cy com~e~l~ arg 3ummed Yi~l ~umm~r 610, tc b~ome
~TMF-~ofma~ed ~ well a~ h~-~pe~ dat~ d ~o~e~. Summgr 610 ~he~
operates a~ ~ ~ta~ ~hich pr~ide~ ~iin.
Thi~ ~ig~alli~ conti~ueg fo~ the u~e~-~ve (voi~) p~tio~ ~f the
telephone in~er~n~ call. By allswin8 receptio~ ~d d~:od~ ~ i~bol~d
data, the pre~e~ inYention allow9 th~ ~ub~iber unit 132, 10~ to be
dy~micaliy ~ntrolled via the ce~tral ~troll~r durin~ ~ c~L This
c~pability imp~o~es call ha~dlin~ ever~ way~. The ~ub~cfiber uniLs c~ll
~tatu~, which is ~t~ed ~d internal~y upd~ted, c~ ~e ch~sed by ~ data
w~d ch~ge ~O~W3 reoeived ~d decoded via prooe~ 614A Fs~ e~ampl~,
a~ ealerge~cy s~atu~ ~itu~tion could override the priority ~ a pho~e call
type and alert ~he operator. Furthe~, tb~ ~ub~criber unit could detect a
margi~al RF ~ig~al esvironment by lo~ of decoded itlbound d~ta; the
receiYer audio from circlJit 608 c~uld be muted Th~ p~e3ent invention al~o
pef mits the ~ub3~iber u~it to a~tomatically terminate the call if a
long-term data los~ i~ det~ted. ï~ addition, the ce~tral con~roller may
terminate ~he ill~erco~ne~ call without w~iting for ~ (sifnple~
dat~-eguipped3 ~ub~criber unit 10~ to 9tOp tra~mitting, si~oe it i9 aware
that the r eque~ti~g subscribel i~ duple~-capable, ag wa~ de~cribed above i~
conjunctio~ wi~h t~e de~criptio~ of Figure 3~. Thi9 dupleY da~a ha~dli~8
capability may improve ~y~tem aCCess delay~ ror interco~ne~ rajl re~ue3~,
~inoe a voice cha~el could ~ubseque~tly be re~3si8ned wi~h lit~le further
C~-Oo 163}~
~p~i~tlo~
y. P~ly, ~ ple3~ 3 o~ ~h~ @~ Y~io~ o~v3
f~ a 3moo~ ~1 ch~nel d~a h~c~o~î ~d/~ inter~n~ call
~inua~o~ (if in pr~re~3 ~ the 3ub~iber unit 104 i~ operati~g in an
a~a hav~ ~ plus~ity of astive tru~ed ~ em~ a9 ~ho~ i~ Figure 1. If
the sub~iber radio 1~ pby~ic~y le~ve~ the ~rim~y ~vera~e are~ ~ o~e
~yg~em ~d e~er~ another ~y~tem capable ~ ~up~in~ gOfm ~
~te~ded c~era~e, th~ curre~t interc~n~ect call can co~tinue with
minlmum h~d~f delay in dat~ a~d voioe ~igIl~lling.
Rcîerrin8 110~7 tO ~iglJfe3 7 ~d 8, th*fc ~ 3hou~ fl~ dia~r~ms
which describe a po~tio~ ~ ~he ct)~trol operatio~ ~ th~ ho~t pr~s~ 61~
~f P~ure 6 a~ it relate~ to the pre~nt i~ventio~. Proce~02 6 l 4 i3 Go3~roUed
by a real-ti~ae, in~errlJpt-dri~e~ pr~8ram sompri~d of Ul i~terrupt serYice
rQuti~e a~d a number of rela~ed bac~grou~d routines (~o~ 3h~n~ ~h~t
control the primary function bei~8 performed a~ a~y o~e ~ime. These
back~rou~d routine~ are relati~ely simple i~ n~ture ~d are u~ed to ac~iYat~
~he method of the prese~t invention a~ well a~ co~trol ~he overall operatio~
of the radio. The ~tructure of the~e background would be obviou~ t9 one 0
ordi~ary skili i~ ~he art and ma~y al~er~ative routine~ would functio~
sati~fa~orily i~ accordanoe wi~h the teaching3 of ~he prese~ inve~tlon
Periodie timcr i~rrupt~ ~o controlled by a i~ernal pr~gramm~ble timer
re~ide~s i~ micr~otnputer 61~.
Ac~di~g ~o Fi8ure 7, rsuti~e 70Q begill~ e~ecu~ion when ~he
microcompu~er 614 intersal timer i:~terval i3 reached. ~ci~ic~ 702
e~amine~ a stored vector which i9 storedl by o~e ~ ~evefal curre~tly
o 1 63N
sps~ 19
_ __
7 .'q~ t' ~
e~u~ed bacJ~ground routine~ ~d i~ eall9eCI lo be ~e~ by th~ radio o~r~l~
re~ue~ DTMP ~rvi~ or by curre~t da~ deco~ bi~ 3yn~ ~a~u~.
~i~is)~ 702 dete~minC9 whuth~r item 70~, 710, o~ deci~io~ 716 is ~o ~e
e~ecuted ne~l. If tr~n3 i~3ion ~2f a DTM~ to~u w~ reque~ted after
receiY~ ~ i~ter~ne~ v~oi~ cha~el ~r~t, initi~lization f~r 20~ m~.
l~w speed ~n~ tone tr~mi~3io~ i~ pro~idedl by i~@ml 7a~. DTMF to~le
~ra~mi3~io~ p~am~r~ ar@ 9Qt Up by ite~a 706, and iterQ 708 re~ume~
~ub~eque~t con~ee~ tone tran~misslu~t a9 i9 ~how~ i~ Pi~ure~ 2~, Line 1.
~nect ton~ i9 both prefi~ed a~d sl.ltfi~ed by DTMF to~es lo e~ure tha~ ~he
oen~al ~ntroller d~ not fal~el~ d~de a lo~ oice cha~el ac~iYity hnd
erro~çou~ly term~te a ca~
~d~io~ 716 i~ 3elected ~eriodica~y to m~t~n bit sy~chro1~iz~io
~ia a 9Cf~YJare pha~e-locked loop or to buffer the latest data bit ~d rec~d
it ~ pa~i~g. Bit sy~ch Yia item9 7?4, 726 and 728 to Ihe co~trol cha~el
data is ac~mpli~d by l~terrupti~g ~he proces~or 614 at t~vi~ the dat~
r~te. Thi~ i~ e~uiYalent to tal~ing t~o ~ample~ per bi~. The ph~ loc~i~g
(clock phase) proce~9 attempt~ to ~ample the bit i~ ~he bit time center a~
well a~ the edge time~. Briefly, the phase-locl~ corr~io~ (~ot show~)
operate~ a~ follow~: If the two mo~t reoena edge 3ample~ are compared. ~d
if fourld to be differe~t, a d~ta edge ~i3t~ betwee~ ~hem. I~ thi~ C~3~, the
state ~ ~he oenter sample determiDes whe~he~ i~ clock phase i~ adYs~oed Of
retarded.
If adjacent ~ample3 a~ree, no incrsme~a5 cl~k phase correcti3n i~
done and it either buffer~ the laaest da~n vi~ 718 or samples ~he ~eoeiYed
~-oo 163H
Spgci~ fi 2D
r~ ~ ? ~
dal~ ~o tes~ ~ a bi~ b~uad~ ~ m 7~ er i~em 718, item 720
updat@~ ~ ~n~er~al 06W bi~ ~u~er w~eae~r a bi~ boll~dary ha3 pa~ed.
Thi~ i~ u3ed for ~ub~ib~ uni~ 10~ ~ychr~atioa rela~iv~ ~o ~he ce~
COD.tfOller~ 110~ outboun~ OSW data w~d boundaries. I~ea~ 722 updat~
thc statu~ of ~y u3er aler~ ~one~ lhat may be curren y b~i~8 ~ener~t~d by
pr~or 61~ and routed ~o a u~ef 10ud~pea~er, then ~ntrol re~ur~ ~o tbe
pre~vioualy-~terrupt@d bac~ground rouline. D~i~i~ 702 ~ele~ item 710,
if nei~her bit sy~c n~r DTMF to~ 9e~ice i9 rcquired. Item 710 upda~e~ ~he
pro~s~or time iIlte~al for ~he ne~t in~errupt, ~d item 712 calJ~e~
~ampli~ ~ the ne~ reoeived data bit via data filte~ 6~ output. Item 714
thell updates ~hç ~lat~ oî a~y a~i~o u3er alert to~ by either t~ling Of
ma~t~8 the curren~ state of tho proce~ 61~ output pOf~..
Rout~ 800 of ~igure 8 i~ the conti~uatio~ o~ e:~ecutiorl give~ deci~io~
702 ~elec~ed item 710. Decisio~ 802 ~elect~ either Item 804, 8û6, 808, 810,
812, 8i4, 816, Of 818 a~ 3et by th~ c~rrespo~ding back~rou~d fOU~ O
aocompli3h a ~pecific periodic tas~. Co~trol may be pa~ed ~o item 804 te~t~
the currently-buîfered reoeiYe data bit~ to determine if the co~trol ch~ne~
~yncha onizatio~ f~ame wa3 r~iYed. The background vector w~
preYiou~ly se~ hers if the radio i~ ~ the quie~cent 9tate on the eontrol data
channel a~tempti~ to remii~ LQ bit and O~iY word ~y~chroni2atio~.
Alternatively, c~n~rol i~ pa~ed to item 806 whe~ there i9 a fleed to
transmit an IS~IV. Cotltrol i~ subseque~tly retur~ed here e~ch ia~errup~
period until the e~tire ISW ig t~ansmitled. Item 80~ i~ e~eelJted ~o de~e~
whe~her high speed ha~ld sha~e data wa~ detected ~n respon~e ~o a c~ntral
OI63~
Sp~ a 2
e~n~roller chamle1 ~raLnt for a di3pa~ch call. If dete~ed, a~
a~ou1ed~eEne~ ~3 i9 ~r~smitted whe~ Ihe curfent1y-e3ecu~ed
ba~grou~d rou~ine ~e~3 ~he L~te~rup~ ve~o~ to poin~ lo iteDl 812, which
would be selected by deei~ion 892. Pr~e~ 614 the~ sarilp1e~ e3ch o~ ~he
cerltral~ tfoll~f ge~eraled bi~s tr~milled via repellter 106. If not
desected, the radio return~ io ~h~ ~o1 ch~ne1 and attempt~
rc~chroniza~ion~
I~em 810 i~ e~ecu~ed for the pfesen~ i~Ye~ whe~ Q duplex
in~rco~nect call grant dire~ ~he ~ub~cfiber UD~ ~o a voioe cha~e1. I~
majoril~y votes these dat~ 3au2ple~, storin8 the voted res~l~ each bi~ time~
temporary regi~ter E~ecuted duri~g the ~m~ i~t~rrupt 3er~ rou~ine
interval i~ item 820 which manage~ the generation ~ 1O~ ~peed c~meGt
to~e which is required by the central controller 11 0 for the prese~t
inven~ion, to ma~ts~n an asiignment to the current voice channç1. Item~
81û and B20 are e~ecuted fM the duration of the u~er-active voioe p~rtio~
of a duple~ Intercon~ect call a~ di~cu~ed abobe i~ conju~ctio~ ~ith Flgure
2~.
Either, item 812 Ol~ 814 i~ e~ecuted during ei~he~ simple~ i~terconnect
or disp~tch caLI ~ype~, deperldin~ upon the unit~ receive or transmit st~te.
Item B12 generste3 either high jpeed, 1OW ~peed, or di3connes~ lone~ for
tran~alis~io~ dependlng upo~ call statu~ a~ de~ibed sbove for i~em 820.
A disco~ect tone i~ formatted ~d tran~ ted upoa de-keying Ihe u~r
tr~n~mit ~witch. Item 8 ' 4 is simil~ to item 820.
I~em 816 forma~ d stores buffered OSW data bit~ for further
~d-00 I 6~H
SPC~ 2
_~L~ P~
deCodi~ ~y ~ b~olmd ~t~/~2 rosJ~e l~.e~a 818 a~fn~iYe~
e~ecuted whe~ ~01~ o~ th~ ~mmo~ ~i~ in Fi~ur~ 7 are required
dur~ the cufre~ errup~ iod. Interrupt 9e~ioe e~ tioa ~erm~ e5
at thi~ poiDt îOr all c~n~ci îl~ p~ di~eu~ b~
Fi~ufes 9, 10, I l, a~d 12 relat~ ~o the ~l~ol fl~ e~ecuted whe~
ei~cr a dispatch ~simple~) or ~ter~ed (~imple~ or duplex3 c~ll typ2
reque~t ha~ bee~ pr~s~ed and voioe-ch2L~el op~ratio~ i~ reQdy to
comme~ with~ ~he ~I-b~criber unit. Co~t~ol i~ tr~erred ~o routine 900
froQl a c~ typ~ e3ecu~iv~ rout~:~e (not 9hown) thllt initi~ ea p~me~rs
te~ed bel~
Briefly, thi~ high level routin~ i~ respo~3ible fo~ direc~ rol s~ce
~he outbound ~ig~aLlin~ wofd dat~ in Figure 2b hag b~rl d~ded. if ~
~ub~criber unit l.D. ma~ fou~d, toutLnes 900, 1000, 1100, and 1200 are
e~ecu~ed ba~ed upo~ data deri~ed from the outbound sigaalling word, ~uch
a3 th~ uiit~ l.D., the ~ype af call, etc., and subscriber u~it hardw~e a~d
optio~ mation ~tored i~ lo~g term memory (i.e. a l;EPROM). RA~
v~isble~ derived from thi3 data are wed to alter the co~trol flcw of she~e
rou~ues1 a~ ~ill be des~ibed below.
Referrin8 now so Figure 9, bacl~ground routine 9~0 be8in~ wi~h
decisio~ 902 to d~tef f~ine whether the curre~ caU-type i~ duple~
intereo~nect. Subscriber unit hardware a~d ~oftware status i~ sypically
ini~ialized fo~ ~imple~ di~patch or Yia ~h~ call type e~ecutive ro~ e. If the
call is dupleg, h~dware i9 ini~ialized to commence operation. Item 904
a~ivate~ tran~ ter circuitry colltrol ~ to in~ure ~hat analo~ circui~
CN-O~ 1~3}~
Sp2c~tlcs~ 23
?p ~3
i9 al~ tdl from th~ qui~ t~ts- Filter~l 606 ~nd 61~ i~ Fi~u~
ac~v~d i~ l~ho l~ 9~St3 d~a ~ lo~ fre~u~e~ mod~.
Item 908 ~e~ temJp~ v~ to e~.ecu~ ~ubroutif~ 810 and the~
820 i~ Fi~ur~ 8. Deci~ioD 910 i~ reach~d ~1l thi3 mahner ~f ~ the call i3
plo~.
Rou~ esecuti~ i~ ~et ~uch shat deu~i~ 910 i~ reaehed e~ch time a
co~apl~e lo~ speed d~a bit ha~ bee~ ed. A ~tat~ rese~ c~ditio~ i~
flag8ed ~ th~ current call h~s been termi~ted. I~ c~se, th~ ro~t~ i~
e~ited a~d c~ol tr~fe~3 to th~ c~ ecutive rou~ . rhe 3ub~riber
u~t lO~ the~ resy~chro~e~ to the ~tral cf~troller co~trol ch~el data
~tres~.
Deci~ion 914 i~ ~elec~ed if a ~t~te re~t fl~ i~ no~ detected. If not,
d~cisio~ 914 s~lec~ routine 1200 in Figure 12 if either a duple~
intercon~çct call or DTMF to~es are required. If the ca~l type i9 simple~,
d~i~ 916 ~e~t~ to det~tmine whethe~ a v~lid pu~h-to-tal~ (PTT) ~tate
e~i~t~. If ~o, deci~io~ 110~ in Figure 11 chee~c~ to ~ee if ~he allow~d
~ren~missio~ ti~ne ha~ e~pired. If thi~ i~ the ca~e, control i~ returned to the
call ~ype e~eeutive rou~i~e to terminat@ the current tra~3mi~io~, and
i~itiate a user ~imeout to~e th~t i~ ac~iYe ~ lonB a~ pu~h-to~ a~serted.
Thia conditio~l is ~to~ed ~i~ item 918.
A~ternativ~ly, if a valid push-to-tal~ co~dltio~ i9 ~ot d¢tected, bu~
decisioll 92û determi~es that D~ torles are ~eeded, it~m 922 ~tores thi3
co~ditio~, ~he rout~ne esit~ via deci3io~ element I 10~ a~d item I 10~ i~
Figure 11, colltrol i~ returD.ed to the call type e~ecutive routine, aIId fi~lly
C~-o~ 1 63R
s~ 24
to ~ ~TP~ tot~e 9e~i~æ rou~e ~o~ ~h~u~3 ~ia~ ~ir~a3 ~h~ mi~roPr~
t~ g~ ss~ t~ ~ p (~ o~p (L.~.) t~ h~ ~h~n
summed via ~ummer 610 in fi~u~e 6. be~me DTM~ lo~e 9i~n3~19.
RoiJtine I~OQ in Figure 10 i~ ~el~cd if the r~ue~ted c~l i9 ~implg~
and no DTMP ~o~ ar~ neede~ d t~e ~u~cri~er u~it i~ ~ reoei~ mode.
Deci~i~s 1002 and I G06 me~sllre ~he ~umber o~ ~e~uentiaJ,
sorre~y-d~oded low ~peet ~at~ w~ le~ ~ha~ ~hree uord~ haYe
bee~ corre~ly decoded, a buf~er is checked f5r ~Wo ~en~ troller^i39lJed
di~nn~tg. If thi~ i~ found to b~ ~ue i~ deci~io~ 1010, conttoi is
tru2sfefred ~o ~ubrou2in~ 1 100, i~em 1 104 3ft~r which D~ appropri~te ~it
statu~ i~ fla8ged via item 1008.
Alternaaively, if deci~ior~ 1 ûû2 d~term~nes th~t ms~e tban t~ word~
~rc erro~eously decocled, item 1004 di~ables ~11 audio outpu~ o the
~ubscf iber u~. The present inve~tio~ wil~ ~ill allow tran~mis~io~ from ~he
sub~criber unit unle~s deci~i~ 1 û06 de~ermL~es th~t mo~e ~han ~i~
incorreclly^decoded ~ord~ haYe pa~ed, else deci3io~ 1010 i~ ag~
e~ecu~ed~ as aboYc.
Then, if two di~eo~ect~ are ~ot pre~ent, ~he previou~ly-buffered data
~e decoded. ~i~io~ 1016 te~ts for a properly decoded en~ire data word.
If o~e i~ nst decoded, ~ ~maller data ~ub-frame i9 ehecked ill a f~al ~ffor~
by deci~io~ 1018 to enable o~ con~ue duple~ receive ~udio. If decislo~
101 & fail~, data bit bufferirlg co~tinue~ i~ the pre~ent i~v~tion as co~rol i~
transfer~ed to rou~i e 900, Figure 9. If the te~ either dec~3ion 1016 or
018 pa~e~, speaker audio is (re3 u~mu~ed, depe~ding upo~ pl'eViGU9
~t~lu~.
C?~ 00163}1
Sp~lcs~ 25
~i r ~ r ~ r ~
o ~.~u~ d~i9i~ 1~ f th~
pre~e~ce ~ a dupl~ c~ t~tu9. If th~ Qt duple2, th~ pre~en~
~ve~ion digable~ tlle trans~itte~ in it~ lQ~, Figur~ 11. A detec~ed
duple~ ca~ cau~e~ t~ol to b@ tra~er~e~ to rollti~e 90~ to ~nti~ue
re~ivi~ d ~ufÇ~rin~ aslditio~al low Yp~l data
Re~ur~g briefly~ to deciiio~ 914 i~ Fi8ure 9, if a duple~ call wa~
det~d, ~trol i~ tran9ferred to rout~e 1200 i~ Fi~ure 12. Sin~e thi~
rout~e can be entered froa~ sever~ other routi~e~, decision 1202 a~a~
test~ f~r a u~i~ 3t~t~ reset. If one i~ f~u~d, co~trol r~tur~ to lh~ call
e~ecuti~e ~outine to termi~ate the curreIlt cull. Deci~io~ 120~ te3ts for, a~d
item 1~06 ~ervi~s a DTM~ to~e ~ervice reque~t if o~ pe~di~g. In ~hi9
fa~io~, multipl~ DTMF tone9 corre~ ding to multi~le ~ubs~ib~s~ key
elosureq ~e proce~ed.
~ eci3io~ 1208 enables the sub~cribef u~t microph~ne audio if the
current call i9 duple2, el~e co~trol tr~fers to decisio~ 916 i~ rou~i~e 900.
1~ Ihe eurrc~t call tran~missio~ tim~ ha~ a pre-s~ tin3eout, sub~terval,
deci~ion 1216 tests to see if thi~ ha~ e~pired. If it ha~ not, the pre~ent
i~vention ~llow9 COn~ft)l tO tran~fer to routille~ 900 ~d the~ to re~urn to
rou~ine 1000, 90 a~ to allow the receiYer contillue to receive and buffer data
from the oe~tral controller concurrent to the pre~e~ly de~cribed
tra~mit~er operation.
If the ~im~ut 3ubin~er~ don~, decisio~ 1218 te~t~ th~ ~r~nsmi~ion
time against the entire timeoult period for completion. If not completed, ~he
routine 1200 repeatedly e3ecute~, after the periodic interrupt 3ervice
OO I 63H
Sp~ill~tl~l~ 26
3 ~ 33
f'OUti~t ig ~ @~ t ~ e~ e i3 ~ via
itl!!fll 12213, ~IYbi~ F'@IU~.9 ~trol ~o routi~ 900. Routi~e 900 i~ turn
t~a~sfers ~rol ~0 rou~ D.e 1 100, ~hieh 3`in~1~y r~tur~ ~ol to ~e call
~ype e~cu~ive rou~e ~ tb~U9 termi~e~ the ~ (dupl~ tra~mit~er
tl~ 9~ pl~ int21~ p~l~t~
In Summ~y, a me~hod ~d m~ chie~ duple~ VOl~
~ntercomlecs over a conve~.tio~al tru~ked r~dlio ~y~t@m h~ b~ de~ibed.
~c~d~ to the teach~ of the p~es~t ia~enti~ According to
~nuplc~ ~ t~ pre9eat iDYentiorl, ~ duple~ c~Qb~ ~wcribor u~it
~o~rates with 8 plur~i~y of duple~ ~un~ed r~pe~te~, a truDki~
co;~trol u~ a ~elcphon~ inter~n~ eo~trol uiit in 8~dD~lGe with
pr~det~mised ~ign~i~g s~eme. Th~ ~ign~ ch~m~ ~ ~h~ p~e~
~nve~tio~ i~ ~tiated by a mobile u~t tra~mit~8 a~ inbou~d 9i$3~
word (ISW) to a c~tral co~trol u~t, o~ a prede~ermiaed freqlle~cy,
whereiQ ~h~ ISW irldicate~ ~ha~ duple~ inter~D~ect call ~efYics h~ be~
requested. The mobile then re~eive~ a~ outbou~d s~alJin~ word (~W~
from ~he central co~trol uiit, wherei~ ~he OS~ constites a 8rant for the
mobile UDit to operate o~ a~ a~si8~sd freque~cy. rhe mobile th~ tra~mits
a con~ect to~e for a predetermined period to the ce~tral cc nt~ol unit, o~
~sigrled freque~cy, while concurre~tly reoeivu~g a low^speed ha~d~ha4e
si~l tr~mitted from the ce~trsl ool~trol uiit. Ne~t, the msbile unii~
concurre~tly trall3mit9 a seque~tial DTMP ~igll~ for a predetermL~ed
period, ~t the termin~tio~ of the co~e~ to~e, while aiso re~ivi~$ a
low-~peed haQd~halce 3ignal, whefein ~he ~T~ ~ig2lal ~mpri~e~ desired
C~-Os 1~3~
27
~elepho~ ~r~ diali~ i~orm~ inally ~curre~tly
traxl~mitt~ a voicg ~d co~e~ ~o~e 3i~rlai while r~iYi~ a Yoi~ ~ig~al
combi~ed wi~h 9~1 low speed hancl~h~ 3~, al the term~a~io~ of ~id
DTMP si~ ~rdingly, o~her u~e~ U16l modificati~ ~ ~he pre~e~t
i~venti~ wiLI be obviou~ to onc ~ or~inary 3kii~ in ~ withou~
depar~ from the ~pirit ~d ~cope of the pte~nt inlYesltiO~.
I Clum:
C~-OO 16.31{
s~i~æ 2
